1. Field of the Invention
The instant disclosure relates to a circuit board structure; in particular, to a manufacturing method of the circuit board structure.
2. Description of Related Art
Under the trend of miniaturization, the overall module packaging of the common electronic products, such as mobile phones or notebook computers, becomes denser. Thus, functionalities of the electronic products are becoming more versatile, rendering larger power consumption which leads to enormous amount of heat generated and the overall temperature to increase. In order to lower the temperature due to overheating, the circuit board tends to be designed with copper (e.g. copper rod or column) thereon as a way to dissipate heat for the electronic components.
Typically, in the conventional method of electroplating a heat dissipating copper column, a two-sided copper-clad laminate of the circuit board is usually drilled through, and the sidewalls of the drilled cobalt holes are electroplated with a layer of copper. However, since copper ions tend to aggregate near the edges of the traces, sidewalls of openings or wall junctions between sidewalls of openings and heat dissipating copper columns, excess aggregation of copper ions tends to form copper lumps at the wall junctions.
To address the above issues, the inventor strives via associated experience and research to present the instant disclosure, which can effectively improve the limitation described above.